Biomedical Computing -- Design and Implementation provides essential computer-related support services to epidemiologist, biostatistician and other Epidemiology and Biostatistics Program professional staff. The contract support data entry and editing activities, file management, software development and analysis and presentation of diverse and large- scale data resources resulting from methodologic and field studies of cancer etiology undertaken by Program investigators alone or in collaboration with extramural investigators in the United States and abroad The computer-related support that is provided falls into three main categories: 1) data management activities; 2) systems design and development; and 3) statistical analysis and modeling. Data management involves keying, formatting and editing data collected from field studies. Systems design and development entail defining technical specification requirements and developing the program language code required to implement automated solutions. Statistical analysis and modeling involve using standard software packages and specialized software to carry out analyses under the general guidance of Program personnel. Total support for any one project often involves aspects of all three contract activities.